1. Field of the Invention
The present invention relates to a magneto-optic disk apparatus in which a magnetic head applies a magnetic field onto a magneto-optic disk of record medium while a laser beam focused in fine beam spot is radiated to the disk, whereby information is recorded or erased, or whereby information recorded in magneto-optic disk is optically reproduced.
2. Description of the Related Art
Magneto-optic disk apparatus can record information at a high density in magneto-optic disk and make access in short time to desired information among information recorded in magneto-optic disk, and have recently been spreading at a high rate. Generally, a magneto-optic disk apparatus is provided with a moving mechanism of magnetic head for taking the magnetic head to the vicinity of a recording surface of magneto-optic disk in synchronism with a loading operation of magneto-optic disk and taking the magnetic head away from the magneto-optic disk in synchronism with an unloading operation thereof.
Japanese Patent Application Laying Open (Kokai) No. 1-130360 describes a magneto-optic disk apparatus provided with a magnetic bias slide mechanism. This slide mechanism is a moving mechanism composed of a pair of rails on which rollers provided in magnetic bias, which is a magnetic head, slide, a lever having a gear at the rotation center and engaging with the magnetic bias at a tip thereof to make the magnetic bias slide by rocking motion, a drive motor for rocking this lever, and a gear train meshing with the gear on the lever to transmit a rotational force of the drive motor to the lever.
In the magneto-optic disk apparatus as described in Japanese Patent Application Laying Open No. 1-130360, however, the magnetic bias slide mechanism needs the drive motor for sliding the magnetic bias and a mechanism for changing the rotational motion of the drive motor to a linear motion, which make the structure complicated. Further, the apparatus is so arranged that the magnetic bias is slid in the radial direction of magneto-optic disk to move between opposing position and non-opposing position to the magneto-optical disk, and therefore a space is necessary for withdrawal of magnetic bias in apparatus to secure the slide amount of magnetic bias in the movement direction. Therefore, it is difficult to make the main apparatus provided with magneto-optic disk apparatus more compact.